Outer cover of airships



June 8 I926. Y 1,588,016

L. DURR OUTER COVER OFv AIRSHIPS Filed Jan. 9. 1925 INVEN'EOR CLAW MM wuw.

ATIVORNEY s Patented June 8, 1926.

UNITED STATES PATENT OFFICE.

LUDWIG DIIBR, OF FRIEDRICHSHAFEN, ."BODENSEE, GERMANY, ASSIGNOB TO L'UFT- SCHIFI'IBA U ZEPPELIN'GESELLSCHAFT MIT BE SCHRANKTER HAITUN G, 01 FRIED- v BICHSHAI'EN, BOIDENSEE, GEIIRLMLAllTY.v

OUTER COVER OF .AIBSHIPS.

Application fled January 9, 1925, Serial- No. 1.399, and in Germany February 11, 1884.

My invention relates to the outer cover of I outer surface which is important with regard to the air resistance. For the pur-' .pose of further reducing the air resistance a coating of varnish is generally apphed. Such varnishing renders the cover practically impermeable to air. The same effect what similar'efiect as well'as ope will occur if, for instance, a metal cover were used. When the airship is in flight,

there will be portions in-the outer cover where the air pressure from the inside andthat from the outside will not be in equilibrium. This will depend on the shape'of the airship body moving through.the air. Increased pressure from the outside will especially be created when the ship is descending from a higher altitude. Also the cowls on the openings for gas esca which are shaped to create a vacuum e ect, will cause a decreased pressure inside the outer Such low pressure inside the ship may easily cause-a rip in the outer cover or even have a bad effect on the hull structure inside.

My invention does away with this'danger by providing adequate openings in the outer cover by which anma into the space confined by the cover and thereby prevent a substantial decrease of pressure inside. I refer to have such openings in the lower orward, part of the airship. A very good way of providirfg such automatically operating openings is to substitute, -woven abric. This will allow a'smooth and ea I way of equalizing the resure inside an outside of the cover. f course, adequate slits in the cover will have a somewhich will be closed un or normal. conditions and open only when a certain decrease of pres sure inside is attained.

automatically flow rtions' ofthe outer cover. by wide- Having explained .my invention ingeneral,I Wlll now point it out in detail referring to the drawing which represents some examples embodying my invention.

'Fig.'1 is a lon 'tudinal section throu h the bow of the alrship, and Fig. 2 is t e corresponding side view. 7 I

The outercover of the airship is designated by the letter a. The hull structure is not shown, except that the structure of a gangway is indicated at Z. There is a clearance between the gas cells I) and the outer cover. Gas passages m lead -to cowls g which are here shown [at the top.

In Fig. 2 a portion h of the outer cover a is made of wide woven fabric, so as to be permeable to air and to allow of aninterchange between the air inside the cover a and the outside air.

Slits i in the outer cover a may serve the same purpose.

The described openings in the outer cover may be situated at any suitable place, but I prefer to have them in the lower part of the ships bow. They will --then operate easily and serve the pur bwt I wafnt it understood that I do lnot limit myself to the examples described or shown.

in the drawing, as many variations will occur to people skilled in the art.

What I claim is 1. In a. rigid airship .an outer coversub- I stantially impermeable-to air, a portion of "said cover being replaced by wide woven airpermeable fabric adapted to regulate diference in pressure occurring between the air outside and the air inside of said cover.

2. In a rigid airship, an outer cover substantially impermeable to air, a portion of said cover being replaced a structure permeable to air but adapt to continue thesurface line of the ship,

whereby air resistance is maintained at a' DB. LUDWIGJDURR.

substantially 

